Ma Kui, Tian Ye, Zhao Zhi-Jian, Cheng Qingpeng, Ding Tong, Zhang Jing, Zheng Lirong, Jiang Zheng, Abe Takayuki, Tsubaki Noritatsu, Gong Jinlong, Li Xingang
School of Chemical Engineering & Technology , Tianjin University , Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300072 , China . Email:
Tianjin Key Laboratory of Applied Catalysis Science & Engineering , Tianjin 300072 , China.
Chem Sci. 2019 Jan 23;10(9):2578-2584. doi: 10.1039/c9sc00015a. eCollection 2019 Mar 7.
Catalytic reforming provides a practical technique for on-board hydrogen production in fuel cell applications. The high energy density, easy transportation and non-toxicity of biomass-derived dimethyl ether (bio-DME) offer potential to replace methanol for on-board steam reforming (SR). Presently, the reaction mechanism over conventional Cu-based SR catalysts remains elusive, limiting the rational design of highly efficient reforming systems. Herein, we build a catalytic system for bio-DME SR with dual-sites of Cu species, , Cu and Cu sites, and achieve a record-high H production rate of 1145 mol kg h. regulating the ratios of the dual-sites of Cu, we clearly describe molecular understandings on SR. And we discover that the substantially boosted activity is induced by a new Cu-determined reaction path substituting the conventional Cu-determined path. Intrinsically, CuO can act as a physical spacer and hydroxyl consumer to suppress the aggregation of metallic Cu species in SR. Due to the unique structure of metallic Cu surrounded by CuO, the catalyst exhibits robust catalytic performance even after severe thermal treatment. These findings open a new avenue for designing efficient catalytic reforming systems with commercial potential.
催化重整为燃料电池应用中的车载制氢提供了一种实用技术。生物质衍生二甲醚（生物二甲醚）的高能量密度、易于运输和无毒特性为替代甲醇用于车载蒸汽重整（SR）提供了潜力。目前，传统铜基SR催化剂的反应机理仍不明确，限制了高效重整系统的合理设计。在此，我们构建了一种具有Cu物种双位点（即Cu⁰和Cu²⁺位点）的生物二甲醚SR催化体系，并实现了创纪录的1145 mol kg⁻¹ h⁻¹的产氢速率。通过调节Cu双位点的比例，我们清晰地阐述了对SR的分子理解。并且我们发现，一种新的由Cu⁰决定的反应路径取代了传统的由Cu²⁺决定的路径，从而显著提高了活性。本质上，CuO可以作为物理间隔物和羟基消耗剂来抑制SR中金属Cu物种的聚集。由于被CuO包围的金属Cu的独特结构，该催化剂即使在经过严苛热处理后仍表现出稳健的催化性能。这些发现为设计具有商业潜力的高效催化重整系统开辟了一条新途径。
